Beacon



FIG. 1 is a top, rear, and left side perspective view of an ornamental design for a beacon;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a right side elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a rear side elevational view thereof; and,

FIG. 7 is a front side elevational view thereof.

The broken line showings of the beacon in the figures form no part of the claimed design. 

CLAIM I claim the ornamental design for a beacon, as shown and described. 